Fabric.



Patented Aug. 8, I899. R. B. SMITH. FABRIC.

(Application filed Jan. 24, 1899.)

(SnacimensJ I: Nmrms vzrzns co, mmournon WASHINGTON w. c.

UNITED STATES ROBERT R. SMITH, OF NEW PATENT OFFICE.

HARTFORD, CONNECTICUT.

FABRIC.

srnozrren'rrolv forming part of Letters Patent No. 630,573, dated August8, 1899.

Application filed January 24, 1899- To all whom it may concern.-

Be it known that I, ROBERT R. SMITH, a citizen of the United States,residingat New Hartford, county of Litchfield, and State of Connecticut,have invented certain new and useful Improvements in Fabrics, fullydescribed and represented in the following specification and theaccompanying drawings, forming a part of the same.

This invention relates to certain improvements in the manufacture 'ofduck fabrics, which while more particularly designed to be" used asfelts for paper-making machines are also useful in laundry-machines andin other situations where a material or fabric of unusual moistureextractive and absorptive qualities is required.

As is well known, in the paper-making art the wet pulp after having beenroughly put" into web form in various ways, according to the style ofmachine employed, passes to the felts, which serve to support and carryit onward as it is subjected to various subsequent paper-makingprocesses. It is desirable to get as much water out of the pulp aspossible while it is on the felt. For this reason, therefore, one of therequisites of a good felt is that it shall have a high absorptive power,so as to take up as much wateras is possible from the wet stock, andthis absorptive power must exist coincidently with strength anddurability. In order, furthermore, that the felt may not leave any markson the paper-stock, it is desirable either to form the fabric with anapped surface in the first instance or else to so make it that it shallacquire as soon as possible a smooth or matted surface-that is, thewarp-threads and the filling which constitute the felt fabric shallbecome so nearly homogeneous that the marks of the weave will not appearon the paper. Finally, since the strain upon such felts or fabrics ispractically wholly in the direction of the warpthreads these threadsshould be formed with the object of withstanding this strain and at thesame time possess as far as is possible the other requirements for afabric of the character described. s v s It is the object of thisinvention to produce a very durable duck fabric for paper-making feltsand other analogous purposes which shall be in a high degree absorptive,so that Serial No. 703.277. (Specimens) it may readily take up the waterfrom the wet paper-stock or other wet material placed thereon and fromwhich after the wet material has been removed the water may be quicklyextracted and the felt dried and so put into condition to receiveanother charge of wet material, and to produce such a fabric cheaply andby ordinary weaving processes.

. Fabrics for the purposes before named and having high absorptivequalities have been heretofore produced, but the goods have been imadeof fine yarn and havebeen woven in two, three, and four plies boundtogether by warp-threads arranged for the purpose. While these goods areefiective for the purpose, the expense of producing them has been solarge asvto practically prohibit their use.

In the fabrics heretofore commonly used for the purposes for which thisinvention is intended the warp-threads have been tightly twisted andsubjected to a hard beaming,with the idea thatthe tight twisting andhard beaming would increase their strength. In practical use, however,such fabrics, and particularly paper-making felts, are in the machinesin which they are employed run over and around a very large number ofrolls that is to say, the fabric in the course of its 1 travel throughthe machine is caused to change its direction of travel Very frequently,

and it is further subjected to considerable manipulation in order to getthe water which ,it has absorbed from the wet material which itcarriesout of it. The result of these frequentTcha'ngesiof direction of travelis of course to cause the fabric to be continually bent andstraightened, and this bending and straightening, together with theother manipulation, cause the several threads which constitute eachtightly-twisted and beamed :warp-thread to Tub or chafe on each other.

The tight twisting and hard beaming, therefore, instead of adding to thestrength of a fabric which is to be used as a paper-making felt or otheranalogous purposes actually weakens the fabric, because the friction andrubbing upon each other ofthe several threads which constitute eachwarp-thread cause them to break, thus weakening the warp, and the fabricsoon becomes useless.

Attempts have also been made heretofore I to produce a fabric for theuses described having a napped surface, such a surface being verydesirable for the production of certain classes of paper. Owing,however, to the hard twist given to both warp and filling, such attemptshave not been successful, as by the time sufficient nap is raised thegoods have been very much weakened, owing to the injury to both the warpand filling threads.

In producinga fabricin accordan cc with my invention instead of tightlytwisting the warpthreads and subjecting them to hard beaming Igive thewarp-th reads as little twist as is compatible with warping purposes2'.e., to enable them to be led from the spools to the beam or loom. Theamount of the twist will vary in accordance with the fabric and stock;

p but it is intended to range from a half to one production of fabric ofthis class.

and one-half turns to the inch,whereas in similar fabrics as heretoforemade the twist has usually been as great as four or five turns to theinch. The warp-threads of my fabric are therefore slack-twisted, and theseveral threads which constitute each warp-thread are as nearly aspossible parallel to each other and as nearly as possible the samelength. The strain upon them is consequently distributed more equallybetween them. Furthermore, as the fabric is bent and manipulated thereis far less chafing and friction between the individ ual threads whichconstitute each warp-thread. The liability of breakage is thereforelargely reduced. It will also be seen that by thus using a slack-twistedwarp-thread I gain in absorptive qualities, since the slack-twisted warpabsorbs water much more readily than a tightly-twisted warp and alsogives it up much more readily.

The filling of a fabric constructed in accordance with my invention iscomposed mainly of rovings. The term rovings is a well-known one in thetextile arts and is used to denote a substantially untwisted assemblageof fibers, the strands of roving being given only a slight twist for thepurpose of enabling the untwisted fibers comprising the strands to hangtogether while the roving is being subjected to the various subsequentprocesses. It is to be understood that the strain in the direction ofthe filling of papermaking felts and similar fabrics is inconsiderable,and the question of strength in this direction does not therefore enterinto the The filling, which is much larger in cross-section than thewarp-threads, is preferably formed of two or more strands of rovingloosely laid around a fine supporting-thread, which I term acarrier-thread. The invention is not, however, limited to any particularnumber of strands of roving. The carrier-thread is not wound upon oraround the strands of the roving in order to hold them together. On thecontrary, it simply serves to support and lead the strands of rovingwhich are wound or laid upon it, as few turns as possible being giventhe strands, and yet cause them to adhere to the carrier-thread and passwith it through the shuttle of the loom. Inasmuch as the rovings are nottwisted before they are wound upon the carrier-thread and are not spunor tightly twisted around the carrier-thread, it. will be seen that thefibers of the cotton which constitutes the rovings are not twisted; butwhen they are in position on the carrier-thread they are as nearly aspossible parallel to each other and to the thread-that is to say, whileeach strand of roving is wound around the carrierthread, yet the fibersof the strands are not twisted, but lie in a fluffy mass on thecarrierthread. It will be seen that a filling of this characterintroduced between the slacktwisted warp-threads before describedproduces an exceedingly flexible and very absorptive fabric. Thepractical absence of all twist in the fibers which constitute thefilling utilizes in the highest possible degree its susceptibility forthe absorption of water and also renders it possible to get the waterout of it much more quickly and thoroughly than would be the case if therovings were twisted before being wrapped around the carrierthread, andthe same is true in a lesser degree of the slack-twisted warp-threads.Furthermore, a fabric composed of a slack-twisted warp and a fillingsuch as has been described assumes the desired homogeneity of surfacemuch quicker than a fabric in which the ele ments are twisted before thefabric is woven. Finally, such a fabric as has been described can bereadily napped, especiallyif the nu n1- ber of warp-threads be somewhatreduced, so as to expose the filling, which can be readily done withoutweakening the fabric to such an extent as to impair its effectivenessfor the purposes for which it is intended.

In the accompanying drawings, which form a part of this specificationand in which like characters of reference indicate the same parts,Figure 1 is a diagrammatic sectional view, on an enlarged scale, throughthe fabric, the plane of section being in the direction of thewarp-threads. Fig. 2 is a section at right angles to Fig. 1. Fig. 3 is adiagrammatic elevation, on an enlarged scale, of the filling. Fig. 4 isa diagrammatic elevation, on an enlarged scale, of the improvedwarp-thread. Fig. 5 is a diagrammatic elevation, on a large scale,illustrating the old form of warp-thread. Fig. 6 is a diagrammaticsectional view, on an enlarged scale, illustrating a fabric constructedin accordance with the invention and having a napped surface.

Referring to the drawings, 1 indicates the warp-threads, and 2 thefilling composed of rovings. The strands of rovings are, as has beenbefore stated, wrapped around an interior or carrier thread 3 with asfew turns as is possible, the arrangement being indicated in Fig. 3. Itis to be observed that the strands of rovings are wrapped around thecarrierthread with long turns and the strands themselves are nottwisted. The result is therefore that the fibers which compose the rovings ICC are not twisted. hen, therefore, the rovings are in place on thecarrier-thread, the fibers which compose the rovings are substantiallyparallel to each other.

The improved form of warp is indicated in Fig. 4. Then this is comparedwith the warp marked 4, (see Fig. 5,) which represents the old form ofwarp, it will be seen that there is much less twist in the new warp andthat consequently the warp is much looser in structure. So far as thefilling is concerned, therefore, nearly the entire absorptive quality ofthe cotton is utilized, and the warp is also much more absorptive thanthe old form. Furthermore, the desirable matted surface is much soonerattained with a fabric of this description, as the warp sinks into thefilling after little use.

In Fig. 6 is illustrated a fabric constructed in accordance with theinvention, the-fabric being here shown as having a napped surface, saidsurface being marked 5. It will be observed that the number ofwarp-threads in this fabric has been reduced as compared with the fabricshown in Figs. 1 and 2, so that the surface of thefillin g is exposed tothe napping mechanism.

What I claim is-- 1. A fabric consisting of slack-twisted warpthreadsand a'filling, the fibers of which are substantially untwisted,substantially as described.

2. A fabric consisting of slack-twisted warpthreads and havinga fillingof rovings which are supported by a carrier-thread, substantially asdescribed.

3. Afabric consisting of warp threads and having a filling ofrovingssupported by a carrier-thread, substantially as described.

4. A fabric consisting of warp-threads and a filling of rovingssupported by an internal carrier-thread, substantially as described.

5. A fabric consisting of slack-twisted warpthreads and a filling ofrovings supported by an internal carrier-thread,substantially asdescribed. g

6. Afabric consisting of warp-threads and a filling of rovings wrappedaround a carrier thread, substantially as described.

7. A fabric consisting of slack-twisted Warpthreads and a filling ofrovings loosely wrapped around a carrier-thread, substantially asdescribed.

8. A fabric consisting of slack-twisted warpthreads and a filling thefibers of which are substantially untwisted said fabric having a nappedsurface, substantially as described.

9. A fabric consisting of warp-threads and a filling of rovingssupported by a carrierthread, said fabric having a napped surface,substantially as described.

10. A fabric consisting of warp-threads and a filling of rovingssupported by an internal carrier-thread, said fabric having a nappedsurface, substantially as described.

In testimony whereof I have hereunto set my hand in the presence of twosubscribing witnesses.

ROBERT B. SMITH.

\Vitnesses:

FRED O. CLARKE, PALMER H. CHAMBERLAIN.

